The present invention relates generally to connectors for optical fibers, and more particularly to a splice assembly for a broken optical fiber cable.
Optical fibers have found substantial use as optical data links in communications systems. Accompanying this use have arisen in the maintenance and repair of fiber optic systems reguirements for devices and methods for rapid, efficient and effective splicing of optical fibers. Consequently, development of fiber optic splices characterized by low optical transmission losses has received substantial attention in the telecommunications industry. Two basic methods for making optical fiber splices have been developed, viz. fusion splicing and mechanical splicing. Fusion splicing involves the exact positioning and melting together of two abutting fiber ends, usually by an electric arc. In fusion splicing of optical fibers within current technology, precise positioning apparatus and relatively large and bulky equipment are required to make splices having low transmission losses of the order of 0.05 dB or less. Mechanical splices, in which the fibers are joined (butted) together but are not melted or fused together, are generally easier to make but usually have optical transmission losses higher than that of fusion splices. In making a mechanical splice, strain relief for the abutting fibers must be provided to keep the relatively fragile glass fibers from being broken by further handling. An enclosure for the splice is usually included in the connecting assembly for retaining the sheathing of the cable in order to accommodate loads which may be placed on the cable.
Tactical fiber optic cable is designed for rugged physical environments. such as vehicle roll-overs and temperature extremes, to which normal telecommunications grade fiber optic cable is not exposed. If a tactical fiber optic cable is damaged in a military environment, it must be spliced quickly and effectively. Ideally, such a splice has low optical transmission loss, is easy to make, and does not require special tools or extensive operator training.
Current practice for field repair of two-fiber tactical fiber optical cable includes use of a splice kit comprising a splicing machine and various hand tools required for construction of the splice, all carried within a 17.times.18.times.15 inch container and weighing about 25 pounds. The splice assembly made using the kit includes a 1.25.times.1.times.10 inch housing and strain relief for the splice requires fastening the synthetic fiber strength members within crimped sleeves. The kit is cumbersome and expensive and requires special tools, precision use and specialized training of operators.
The present invention provides assembly and method for splicing a broken fiber optic cable under severe field service conditions without expensive complicated or heavy tools or equipment. Splicing optical fibers according to the invention is performed by cutting away portions of the cable to expose the broken ends of the optical fibers, cleaving the fiber ends and adhesively fixing the ends in abutting relationship within elastomeric, tubular splice assemblies, and fixing the splice assemblies within plastic or epoxy material in a two-part protective housing. The splice may be made by a minimally trained operator in 15 minutes or less, and is usually characterized by a transmission loss of 0.5 dB or less.
It is therefore a principal object of the invention to provide a connector structure for splicing a broken optical fiber.
It is a further object of the invention to provide a rugged, inexpensive and easily assembled splice for field repair of a fiber optic cable.
It is yet another object of the invention to provide a simple and effective method for rapid repair of fiber optic cables.
These and other objects of the invention will become apparent as the detailed description of representative embodiments proceeds.